Well drilling apparatus



W. W. SPACEK WELL DRILLING APPARATUS June l5, 1954 3 Sheets-Sheet l Filed July 18, 1949 Spacek Wil/lam Warren June 15, 1954 w. w. sPAcEK WELL DRILLING APPARATUS 3 Sheets-Sheet 2 Filed July 18, 1949 Fig. 8

Fig. 7

Fig. /0

SWW/wit Wil/iam Warren .Spacek June 15, 1954 w. w. sPAcEK WELL DRILLING APPARATUS 3 Sheets-Sheet 5 Filed July 18, 1949 Fig. I4

IIIIII Fig. /2

INVENTOR. MII/am Warren Spacek BY fum/3. w

Patented June 15, 1954 UNITED STAT OFFICE 8 Claims.

This invention relates to a method of drilling wells, as oil or water wells, and to a bit assembly structure designed therefor so that the bits thereof may be changed when desired by moving the bit assembly up and down the drill stem without having to remove the drill stem from the well.

It is an object of this invention to provide a drilling method and a bit assembly structure therefor which may be moved up and down the drill stem employed in the rotary method of drilling wells, so that the bits of the bit assembly may be changed Without the necessity of having to remove the drill stem from the Well.

It is a further object of this invention to Pro- Vide a drill bit assembly of this class adapted to drill an oval hole.

It is also an object of this inventionto provide a drill bit assembly of this class which is adapted to drill a round hole.

It is a further object of this invention to provide drill bit assemblies of this class which are adapted to be operated on the drill stem without interfering with the fluid circulation therethrough.

t is also an object of this invention to` provide a method of drilling and a drill bit-assembly structure therefor which requires a much lighter rig for the ordinary handling thereof than is required in present day conventional drilling methods.

It is another object of this invention to provide a drilling method and a drill bit structuretherefor which is designed to save the great amount .of labor now expended on conventional rigs which require that the whole drill stem be removed from the Well every time the bit is to be changed.

It is yet another object of this invention to provide a drill bit structure of this class designed to eliminate the drill stem back lash now encountered in conventional equipment.

It is yet a further object oi this invention to provide a Structure of this class which is better adapted than conventional structures to permit the quick and easy taking of cores, and running of other essential tests.

It is another object of this invention to provide a drill bit structure of this class having a transmission included therewith adapted to deliver more power to the bits When driven by a smaller size drill stern than the drill stem required for the delivery of the same power by conventional equipment.

Other and further objects will be obvious when -the specication is considered in connection with `the drawings, in which:

Fig. l is a sectional elevation through one modi- 2. cation of the bit assembly and part of the drill stem;

Fig. 2 is a sectional plan View taken alongline 2--2 of Fig. 1;

Fig. 3 is a sectional plan View taken along line 3 3 of Fig. 1;

Fig. 4 is a sectional bottom View taken along line l-il of Fig. l;

Fig. 5 is a side elevationtaken along line 5- 5 of Fig. 4;

Fig. 6 is a sectional elevation showing the lowering or landing spear;

Fig. 7 is a sectional elevation showing the elevating spear;

Fig. 8 is a side elevation showing the reamer construction;

Fig. 9 is a bottom View taken along line 9-9 of Fig. 1;

Fig. 10 is a diagrammatical'view showing the substantial contour of the hole cut by the bits ,of Fig. 1;

Fig. 11 is a sectional elevation showing a second modification of the drill bit assembly and part of the drill collar structure of this invention;

Fig. 12 is a side elevation taken along line I2-I2 of Fig. ll;

Fig. 13 is a diagrammatical View showing the contours of the holes cut by the bits of Fig. l1; and

Fig. 14 is a sectional elevation taken along line lil-ld of Fig. 11 showing the connection of the drill collar on which the bit assembly is mounted to the tool joint and drill stem section thereabove.

In the conventional manner of drilling wells by the rotary method the drill stern employed usually consists of pipe sections connected by tool joints of larger diameter than the pipe and near the lower end or the drill stem a drill collar or a number of such collars is added. These collars being of the diameter of the tool bits thereabove or larger.

Finally the bit which drills the hole Whichis of substantially larger diameter than the drill collar is installed on the end of the drill collar. The Whole drill stem is o1" tubular construction so that fluid may be picked up from the mud pit at the top of the well, circulated downwardly therethrough and out through the bit from where it passes upwardly through the annular space between the walls of the bore which the bit has drilled and the drill stem and is circula-ted outwardly from the top of the well to the mud pit.

With conventional equipment when the bit becomes dulled as occurs periodically due to the hardened earth formations through which it must 3 drill, it becomes necessary to change the bit. This is accomplished by the laborious process of withdrawing all of the drill stem from the well section by section and then replacing it section by section and more time is expended in making such changes, termed trips into and out of the well than in any other one drilling operation.

With the apparatus of this invention the necessity of removing the drill stem every time the bit has to be changed is eliminated by providing a bit assembly which may be pulled up over the drill stem and slid back downwardly thereover; the drill stem remaining all the time in the well.

In the form of the invention disclosed in Fig. i the drill stern l is comprised of flush joint type pipe which is of a uniform outer diameter throughout the length thereof and which has the joints between sections extended inwardly. The lower section 2 of this drill stem need be modified in only three small particulars to adapt it for use with the bit carrier assembly 3. Such adaptation consists in providing the lreyway indentation or lock port i therein; providing the annular slotted ring which is rigidly connected to the drill stern exterior near the bottom thereof, and in providing the nozzles E at the rounded lower stem end through which the mud or circulating fluid is discharged.

The bit carrier assembly 3 includes an inner element which may be termed the transmission, or transmission assembly which is enclosed and journalled in the housing 3. The central member of the transmission is the power tube 9 which is of an inner diameter to slide over or have a slip fit with the drill stem 2 and which has thereon the spur gear H, the rings l5 and i6 mounted thereon to rotate in the bearings Vi and i8 respectively of the housing 8 and at the lowest point of the power tube the lock I9 is provided to fit in the slot 2l of the ring 5 on the drill stem 2; the power tube being beveled at 22 to mate with the bevel 23 on the ring 5.

The drive sleeve le nts over the power tube 3 and has thereon the spur gears l2 and i3 and the bevel gear It. This sleeve is journalled in bearings 33 and 3l of the housing 8.

The power tube 9 terminates upwardly in a cylindrical head 2li which has the ring 28 thereon to rotate in the bearing member 29 of the housing S. A sleeve or collar member 2S, which may be a composite element as shown or optionally a casting, is adapted to slide between the head 2Q and the power tube 9. This member has the stop ring 25 on the cylinder 2l thereof to lodge against the shoulder 3D when the member 2t is in upper position. A plunger ring 3l is mounted to slide within the annular projection fail of the member 26 and this ring 3l cooperates with the Spearhead or spear engaging shouldered formation 33 of the member 26, as will be hereinafter described, to release the bit assembly 3 after it has been lowered into the well. A radially projectible key or lock 3d is brought into engagement with the power tube 3 by means of the spring 35. When the collar or tubular member 28 is in lower position the skirt extension or cylinder 21 thereof forces the lock 3i into the lock port or keyway i of the drill stem l to lock the power tube 9 and drill stem together to prevent any relative longitudinal movement, and when the member 26 is in upper position the lock 34 is urged outwardly by the spring 35 to disengage these two elements.

The spur gear ll on the power tube 3 meshes with the spur gear 39 on the shaft ci which is journalled within the bearings l2 and 43 of the housing 8 and which has the spur pinion tl on the end thereof. This spur pinion M, in turn, meshes with the spur gear i5 on the shaft d6, which is journalled in the bearings il and 43 of the housing 8, and which has the spur pinion 139 on the end thereof to mesh with the spur gear i2 on the drive sleeve l0.

The spur gear I3 on the drive sleeve i0 drives the pinion 52 at the top of the bit shaft 5S and through the idler 5ft it also drives the pinion 55 at the top of the bit shaft -53 with the result that, as shown in Fig. 9, the bits E and 53 rotate in opposite directions and in timed relationship so as not to interfere in operation.

Bearings 39, 6l, and 32 are provided in the housing 3 for the bit shaft 5'5 and bearings 63, Sii, and 65 are provided therein for the bit shaft 53. The seals 33 and 67 are also provided within the housing 8 to seal around the power tube 9 near the top and bottom thereof respectively.

The bevel gear Hi meshes with bevel pinions 'I0 and H and the shafts l2 thereof are journalled in the bearings 5B of the housing 3 and have mounted thereon the reamers 'i3 and Hl as shown in Fig. 4. These reamers, shown in side elevation in Figs. 4 and 8 and in plan in Fig. 5, each comprise four radial arms spaced 90 apart. Co-operating with each reamer is a cleaner it also comprising four radial arms, journaled for rotation on the housing 8 with the arms thereof in mesh with the reamer arms so as to extend into and move through the spaces between the reamer arms for pushing out and keeping down accumulations of material reamed away from the bore wall. The cleaners 'i5 do not engage the bore wall, and therefore are of lesser height transversely of the carrier than are the reamers "i3, as clearly shown in Fig. 8.

As shown in Fig. 2 the housing 8 is of substantially oval cross-section and in addition to serving as a housing or journal member, is itself a guide means, and has the ns or guides i05 thereon; there being of necessity an enlargement l to permit the installation of the necessary transmission elements in the housing. As shown in Fig. 3 the cross-section is modified from that of Fig. 2 to permit the installation of the reamers 'i3 and lil and reamer cleaners i5 on the housing.

As shown in Fig. 10 the bit 3i cuts a circular hole il@ and the bit 58 cuts a circular hole IH, there being an overlapping area H2 common to both bit holes. The reamers 'i3 and 'ill out out the formation sections H3 and H respectively and thereby round out the oval contour of the hole down through which must pass the housing 8 with the guides H15 thereon.

A spear or suspension coupling 8E is provided as shown in Fig. 6 which has a body Si consisting of a central tube 82 and an outer housing 83 which is connected to the tube as by the plates Si at the top thereof. These plates have holes 85 therein to receive lines 83 by which the suspension coupling or spear Bil may be lowered or raised over the drill stem l. Spear arms 8l are pivctaily connected at 88 to the housing 83 and slots 8S are provided in the housing so that the arms 87 may be moved outwardly therethrough. Normally the arms 87 are urged inwardly by springs 9i which are attached at 92 to the tube 32 and at 133 to the arms. This type of spear is termed a landing or lowering spear and each arm 81 has a barbed point 93 thereon of triangular cross-section which is adapted to have the barb Q4 thereof fit under the top 95 of the spear head 33 of the bit assembly 3 when the bit assembly 3 is loweredinto the well. The hypotenuse face 95 of the barbed point is in contact with the hypotenuse face 91 of the plunger ring 3| when the bit assembly 3 is being lowered. When the bit assembly 3 comes into contact with the ring 5 at the bottom of the drill stem, the housing 8 and power tube 9 are stopped, then when the spear 80 is further lowered, the plunger ring legs 90 contact the housing top and the plunger ring 3| is moved upwardly to force the arms 81 outwardly against the inward urging of the springs 9|, and this releases the spear 80 from the spear head 33 so that the spear may be slid upwardly over the drill stem to the top of the well.

When it is desired to raise the bit assembly from the well a spear |04 is provided which is essentially like the spear 80 with the exception that the spear points thereof are of a crosssection to permit the barbs 94 thereof to engage under the top 35 of the spear head 33 without ever coming in contact with the plunger ring 3|, even when the member 26 is in its lowest position.

When the bit assembly 3 has been lowered until it contacts the ring of the drill stem the lock 34 on the power tube 9 is not necessarily brought into engagement with the lock port 4 in the drill stem but is confined between the cylinder 21 and the power tube 3. Also,y the lock le of the power tube 3 is not necessarily in engagement with the slot 2|, as shown in Fig. 1, but may be at some point along the beveled surface 23 of the ring 5. It then becomes necessary to apply a slight amount of rotation to the drill stem to move the lock I9 into engagement with the slot 2| and this also brings the lock 34 within the lock port 4.

rlhe modied form of the bit carrier as shown in Figs. 11-14, is designed to eliminate the gearing required in the modication hereinabove disclosed and this elimination of gearing permits the central element or power tube to be constructed of a larger diameter tube than the power tube 9 disclosed in Fig. l. Such a power tube |20 must be of a size to slide over and have a slide t to the drill stem |2| and the tool joints |22 which connect the drill stem sections, and also such a power tube |20 must be constructed of a diameter to slide over and have a slide t to the drill collar |23. This drill collar |23 terminates in the rluid outlet element |24 which has the fluid ports |25 therein, and which also has the ring |26 corresponding to the ring 5 on the drill collar |23. The power tube |20 is brought into locked engagement with the drill collar |23 in the same manner as the power tube 9 is locked to the drill stem The construction of the spear head or releasable formation 33 and the upper part of the housing |28 is similar to the construction of the corresponding members described hereinabove and shown in Fig. 1 and the same reference numerals are assigned thereto. The housing |28, having no gearing therein, has only to provide the bearings |3| and |32 in which the power tube rings |33 and |34 may rotate respectively. The rings |33 and |34 are fixed to the tube |20, and the tube housing assembly constitutes the carrier assembly for the bit unit.

With this modification an adapter |35 is rigidly fixed to the power tube |20 and the bit socket |36 is threaded thereon. Bits |31 and |38 are formed integrally with the bit socket and in Awith the housing |28 drilling cut out and annular space |40 der'ied by the outer diameter |4| of bits |31-and |38 and the diameter |43 of the points |44 of the slotted bits |45. As shown in Fig. 11 these slotted bits |45 are pivotally mounted on the bit socket |36 and the angle thereof is set by means of the screws |41. As shown in Fig. 12, the slots |5| in each slotted bit |45 are of a size to permit the bits |31 and |38 to be pivoted therethrough.

not having the transmission of the iirst modification, does not eliminate back lash, and is limited to rotate at the same speed that the drill stem -is rotated, however it has the advantages of being adapted for use on the conventional drill stem in which the pipe sections thereof are made up by the use of conventional tool joints |22 and therefore a stronger type of drill stem may be employed than the flush joint type of drill stem required by the rst modification described hereinabove. The elimination of the transmission permits the use of a smaller housing |28 and therefore a smaller bit construction may be employed, so that less power is required to drive Such bit construction through a stronger drill stem.

Obviously the guides or hns |35 shown rigidly connected to the guide means or housing |23 in Fig. l1, serve the same purpose as the guides |05 shown in Fig. l, that is, these guides rotate as it rotates through frictional engagement with the well bore, and thereby tend to achieve and maintain a clean, enlarged, straight bore, as they follow downwardly after the bits, as the bore is drilled thereby.

It is herein pointed out that whereas bits of a specific configuration,l as those of the bits 51 and 58, have been shown, this invention is not limited to bits of this type alone but any type of conventional bit or modification thereof may be employed with the apparatus of this invention and results may be accomplished thereby comparable to the results which can be accomplished by the structures disclosed.

It is also pointed out that whereas the word transmission has been used generally to include all the elements interposed between the drill stem and the bits and whereas the Yterm power tube has been limited to a specic structure as has been the term drive sleeve, these terms may be employed interchangeably to designate the means by which the drill stem transmits its rotational force to the bits.

The structures disclosed hereinabove are not the only structures adapted for employment in an apparatus which will enablebits to be changed without removing the drill stem from a well and this invention broadly lays claim to any structures other than those disclosed which are adaptu able to work within the broad method to which the apparatus hereinabove described has an application.

Broadly this invention considers a drill stem and bit assembly therefor and a method of drilling which does not require the removal of the drill stem in order to change the drilling bits employed thereon.

What is claimed is:

1. In a drill stem and bit assembly employed in the rotary method of drilling wells, the combination of, a bit assembly adapted to be slid over said drill stem, said bit assembly including, a housing and a drive ratio modifying a transmission journalled for rotation in the housing in oiset relation with the drill stem, bit means driven by said utransmission .for drilling a '.hole, and means for releaseably llocking lsaid transmission to said drill stem for drive therefrom releasably.

2. Ina drill stem and bit assembly 'employed in the rotary method of drilling wella'thegcombination of, a bit assembly including, ia .housing and a speed changing transmission .journaled Vfor rotation therein, said transmission .including .a power tube adapted to be slid over saiddrill stem, bit means driven by said transmission for drilling a hole, means for locking said ltransmission to said drill stem for rotation therewith.

3. In a `drill stem and .bit assembly employed in the rotary method of drillingwells, the combination of, a bit assembly adaptedutobe slid over the drill stem, said bit assembly including, a change speed transmission, a 'pair of bits substantially equally and diametrically spaced apart from the axis o said drill stem being of larger radial dimension Vthan the radial distance from bit axis to stem axis, said l:bits being connected to the lower end ofsaid transmission one to follow the other vover the common transverse area swept by both in rotation, of reamers substantially diametrically V'opposed across said stem axis above and at substantially right angles to said bits and connected 'to .be driven by said transmission to traverse areas -to complete the total cross-sectional area boundary I.'

traversed by said bits and said :rea-mers as a substantial oval, a housing surrounding said transmission and to provide the rictional support in which said tr-ansmission may rotate., and means to establish a driving engagement between said drill stem and said transmission.

4. Well drilling equipment, including a rotary drill stem having a keyvvay near its lower end, a drill bit carrier assembly sleeved on said stem by a slip iit for lowering and raising the carrier while the stem remains in the wellbore and comprised of an outer guide and bit centralizing tube and an inner bit supporting tube and rotary bearings spacing said tubes and accommodating their relative rotation, a radially projectible key mounted on the inner tube 'for co-operation with said keyway to releasably lock the stem and inner tube in drive relation, an axially adjustable collar engageable with said key to control its projection into and out oi the keyway, and a formation on said collar for releasable connection with a suspension coupling for lowering and raising the drill bit carrier assembly.

5. Well drilling equipment, including v-a rdrill stem, to enable the carrier to be lowered and raised in the well bore, without displacement of the drill stem, said bit carrier including a central stem driven member, a well bore engaging and bit centralizing spacer rotatably locating the driven member sleeved'on the stem, 4means releasably drive connecting the driven member .and

driving stem comprising la keyway :in one Aand a -and each bit a pair a bit carrier having a slip fit on the stem radially .projectible key V.inthe other, anda-key actuating 'shoe shiitable 'axially oi the driven member '.-to control the VVprojection and retraction of the key'into-and-out of drive transmitting reception in said keyway.

6. Well drilling equipment, including a drill stem, a bit carrying sleeve vhaving a slip fit on the stem for raising and lowering the sleeve while the stem remains in the lwell bore, a spear engaging head having limited :axial travel Aon said bit carrying sleeve, a'key for drive coupling'the sleeve with `.the stem and operatively related to said head for uncoupling Vthe drive when the head is raised relative to the sleeve and for coupling the drive'lwhenthe head is lowered relative to said sleeve.

7. In a well driilingbit -carrier for application to and .removal from a drill string while `the string remains in a well bore, a ybit mounting sleeve arranged for a slip fit on the drill string, a spear engaging .head surrounding the top of said sleeve and having .limited adjustment axially thereof from 'a raised to a lowered vposition relative Ito said sleeve, and a spring mounted retractable key carried `by the sleeve in the path of said head so as to be ylocked in drive coupled relation with the drill string when the head is lowered on the sleeve and to be sprung out oi drive coupled relation when the head is adjusted to its upper limit.

8. 'In a well drilling bit carrier to be slip iitted to a drill string for raising and lowering the carrier without raising Aand lowering the drill string, .a driven tube, -a spear engaging head telescoped on the upper end of the tube, limit stops onthe head and t be for suspension engagement when the head is raised to its upper limit, la spring retracted drive key carried by the tube in the downward path of said head for projection by the head into drive coupling relation with the drill string.

References Cited in the .ille of this patent UNITED STATES PA2[llll'\l'IS Number Name vDate 1,068,015 Stewart July 22, 1913 1,419,068 McFadden June 6, 1922 1,524,776 Boland et al Feb. 3, 1925 1,530,803 Anderson Mar. 24, 1925 1,562,449 Herrin Nov. 24, 1925 1,612,338 Wilson et al. Dec. 28, 1926 1,696,576 Jones Dec. 25, 1928 1,771,066 Stokes July 22, 1930 1,777,961 Capeliuschnicoi Oct. 7, 1930 1,824,466 Cr'iley Sept. 22, '1931 1,853,249 Scott et al May 17, 1932 2,128,102 Sherman Aug. 23, 1988 2,151,646 Subkow et al Mar. 21, 1939 2,463,420 Prassel Mar. 1, Ai949 FOREIGN PATENTS Number Country Date 887,242 France Nov. 8, 1943 

